Primary Data Source: ODOT crash data, 2007-2014 -- incidents on the roadways reported from law enforcement, emergency responders, and motorists.
Warning: relies on driver reports for less serious incidents, thus may be missing crashes that cause no injury and little damage. Also missing may be crashes that are in progress of litigation or otherwise being investigated.
For many purposes, crash data should be viewed as a rate - a rate per capita or rate per vehicle miles traveled - and this data portal provides information about rates, as well as actual counts.